Commands by smolav (2)

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commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Get file access control list

Speed up or slow down video (and audio)
Usage: videospeed video_filename speedchange newfilename videospeed foo.mp4 0.5 foo_slow.mp4 Range of 0.5 (50%) - 2.0 (200%) is valid.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Add a line from 1 file after every line of another (shuffle files together)
After every line in targetfile (empty lines included) insert in a line from addfile. "Save" results to savefile. Addfile should be longer than targetfile since this doesn't loop back to the top of addfile. /^/R addfile -- says for every line that matches "has a start of line" output a line from the file addfile. > savefile (optional) -- redirect output to savefile file.

[vim] Clear trailing whitespace in file
% acts on every line in the file. \s matches spaces. \+ matches one or more occurrences of what's right behind it. Character '$' matches end-of-line.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Convert unix timestamp to date

List all duplicate directories
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical. if in doubt apply: $ diff -rq path_to_dir1 path_to_dir2 AWK function taken from here: http://stackoverflow.com/questions/2912224/find-duplicates-lines-based-on-some-delimited-fileds-on-line


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